Telecommunication frequencies refer to the range of electromagnetic waves used for transmitting information over distances. These frequencies are part of the radio spectrum, which is divided into various bands, each serving different purposes and applications. Below is a detailed table comparing the key frequency bands:
| Frequency Band | Frequency Range | Wavelength Range | Common Applications | Characteristics |
|---|---|---|---|---|
| Very Low Frequency (VLF) | 3 kHz to 30 kHz | 100 km to 10 km | Submarine communication, navigation, and geophysics | Long range, penetrates water and earth |
| Low Frequency (LF) | 30 kHz to 300 kHz | 10 km to 1 km | AM broadcasting (long wave), navigational beacons | Long range, stable propagation |
| Medium Frequency (MF) | 300 kHz to 3 MHz | 1 km to 100 m | AM broadcasting (medium wave), maritime communication | Moderate range, subject to interference |
| High Frequency (HF) | 3 MHz to 30 MHz | 100 m to 10 m | Shortwave broadcasting, amateur radio, aviation, maritime | Long-distance communication via ionospheric reflection |
| Very High Frequency (VHF) | 30 MHz to 300 MHz | 10 m to 1 m | FM radio, television broadcasting, two-way radios, aviation | Line-of-sight communication, limited range |
| Ultra High Frequency (UHF) | 300 MHz to 3 GHz | 1 m to 10 cm | Television broadcasting, mobile phones, GPS, Wi-Fi | Line-of-sight, higher bandwidth, limited range |
| Super High Frequency (SHF) | 3 GHz to 30 GHz | 10 cm to 1 cm | Satellite communication, radar, microwave links | High data rates, line-of-sight, affected by obstacles |
| Extremely High Frequency (EHF) | 30 GHz to 300 GHz | 1 cm to 1 mm | Advanced radar, scientific research, high-frequency data links | High data rates, line-of-sight, sensitive to atmospheric absorption |
Summary
- Very Low Frequency (VLF): Used for submarine communications and navigational aids due to its ability to penetrate water and earth.
- Low Frequency (LF): Primarily used for AM broadcasting and navigational beacons, offering stable propagation and long-range communication.
- Medium Frequency (MF): Commonly used for AM broadcasting and maritime communication, offering moderate range but subject to interference.
- High Frequency (HF): Utilized for shortwave broadcasting and long-distance communication via ionospheric reflection, ideal for aviation and maritime communication.
- Very High Frequency (VHF): Used for FM radio, television broadcasting, and aviation communication, offering line-of-sight communication with limited range.
- Ultra High Frequency (UHF): Employed in television broadcasting, mobile phones, GPS, and Wi-Fi, providing higher bandwidth and line-of-sight communication.
- Super High Frequency (SHF): Applied in satellite communication, radar, and microwave links, allowing for high data rates but affected by obstacles.
- Extremely High Frequency (EHF): Used in advanced radar systems, scientific research, and high-frequency data links, providing very high data rates but sensitive to atmospheric absorption.